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III. General Characteristics of Modern Farming

III. General Characteristics of Modern Farming

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188



It. W. EtURLBUT



comparative values are 1058,1066, and 1064, respectively. On this basis,

it is evident that whereas we North Americans have been successful in

making it possible for one worker to accomplish much more than i n other

parts of the world, we have not been so successful in increasing the yields

per acre.

3. Inzpwt of a 20 Per Cent Increase i n Total Farm Ozltptlt



A summary of reports of forty-eight state committees, United States

Department of Agriculture Information Bulletin 88 (1952), appraising

the productive capacity of agriculture during a subsequent five-year

period, indicates that a total farm output about 20 per cent greater than

that of 1950 could be attained under “average” or reasonably favorable

conditions. It is further estimated that about 44 per cent of the projected increased output potential exists in the South, about 41 per cent

in the North Central Region, and about 5 per cent each in the Northeast,

Mountain, and Pacific regions.

Production of feed and livestock would be expected to make u p a

major part of the increased output in all regions and 58 per cent of the

increased production for the country as a whole. Food grains would

represent about 15 per cent of the projected increase for the nation as a

w:iole; fruit, truck, and vegetable crops, about 9 per cent; and cotton,

about 5 per cent.

A projected increase of 20 per cent above the total farm output in

1950, without a substantial increase in the farm labor force, is estimated

to require about five or six times as many cotton pickers ; more than twice

as many forage harvesters ; 30-50 per cent more balers, power sprayers,

beet harvesters, and power manure loaders ; 20-25 per cent more mechanical corn pickers and combines; and about 13 per cent more milking

machines and silos. These estimates do not include the need for machines

to replace those discarded because of wear or obsolescence.

It is estimated that a 70 per cent increase in commercial fertilizer

would be required to help produce the projected increases in yield. The

estimated potential maximum yield per acre of major crops and pasture,

as a percentage of the 1950 yields (adjusted), is corn, 167 per cent;

sorghum for grain, 124 per cent ; soybeans, 141 per cent ; peanuts (picked

and threshed), 183 per cent; cotton (all), 176 per cent; wheat (all),

140 per cent; rice, 120 per cent, hay (all tame), 156 per cent, rotation

pasture, 197 per cent. Although these production estimates bear both

theoretical and practical implications, they do show a relatively wide

gap between current crop yield expectancy under prevailing .practices and the yields that could result if farmers were using the known

improvements that would be profitable under reasonable economic condi-



PROGRESS IN AQRICUbTURAL ENGINEERING



189



tions. This gap presents a real challenge to agricultural research, education, and extension programs. On the other hand, the fact that the

estimates indicate a practical total agricultural output of one and onehalf times that of the record year 1951 is, in itself, a real tribute to

agricultural research. It also is good evidence that modern American

agriculture is the most dynamic the world has ever known.

Farming tomorrow must be done more scientifically, and more precisely, than it was yesterday. This means that in the future even more

emphasis must be placed on increased production, improvement in quality of products, better management, better equipment, and better living

conditions for farm people. Better control over the factors influencing

agricultural production will continue to be the principal joint objective

of agricultural engineers and agronomists.

4. A Pew Important Developmennts, 1900-1950



The record of new developments during the past fifty years makes it

seem almost futile to attempt to forecast developments or trends beyond

the next decade. As a prelude to consideration of trends in agricultural

production, it seems proper to review briefly a few of the results of our

efforts to gain a more abundant life during the past fifty years. We

already are taking for granted some of these relatively new developments which have exerted and still are exerting a tremendous influence

on our well-being and on our pattern of life. Although the basic inventions of these developments were of earlier conception, their practical

applications have come in recent times. A few of these developments are :

1. The use of power and machinery in agriculture, which has reached

the point where 85 per cent of the people in the United States have been

released from the task of producing food. This has made possible our

great industrial development and the correspondingly great increase in

service occupatiom.

2. Telephones and other means of direct communication, which multiply human contacts and speed u p business transactions.

3. Motion pictures with sound and radio and television, which serve

well for disseminating information and providing entertainment.

4. Airplanes, which are now beginning to play a n important part in

agricultural production.

5. Electricity, for light and power, now provided on a high percentage of the farms in the United States.

6. Mechanical refrigeration for the preservation of the perishable

agricultural products.

7. Pavement on the main routes used by vehicles.



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L. W. HTJRLBUT



8. Hybridization in farm crops and greatly improved breeding and

feeding practices i n the animal enterprises.

9. Widespread use of chemical fertilizers.

10. Basic practices for use in reducing water runoff and the closely

related erosion of soil.

11. Transportation of liquid fuel over long distances in pipe lines.

12. Development of water resources for irrigation.

What will be the comparable developments in the second half of the

century? Is it proper to say that new developments will come as rapidly

and be of more beneficial influence than those of the first half of the

century ? Some people are inclined to think that technological advances

are f a r outdistancing the developments in the social structure of the

world. Certainly we cannot overlook the importance of the “human factor” in considering future developments. However, there is little concrete evidence to indicate that both technological and social advances

will not continue a t an accelerating rate.

IV. FUTURE

TRENDS

1. Farm Power



A t least two kinds of power are available on about 88 per cent of the

farms in the United States, namely, mechanical power and electrical

power. Although both sources of power are very useful, both have certain limitations.

a. Tractor Power. Tractors of today have too few power outlets, and

as a result they frequently remain idle while the operator serves as a

source of power. On the other hand, electric power can be applied to

many jobs on the farm, but it is limited to a n area around the meter

pole approximately 400 feet in radius. Another limitation on the use

of electric power furnished by rural lines is unscheduled interruption

of the supply. The limitations now recognized in the two power sources

for the farm indicate that a combination might be most useful. An

engine-electric tractor would have numerous power outlets ; it would

make some of the automatic features of electric power useful on field

machines; and it could serve as standby power in case of interruption

of the electric service,

The electrical generator and the electrical motors required for use in

an engine-electric power system present some difficult design problems,

but the problems appear to be subject to reasonable solutions. The cost

of such a system appears to be an unreasonable handicap until the pres-



PROGRESS IN AGRICULTURAL ENOINEERINQ



191



ent investment in engine-units standing idle on idle farm machines is

fully recognized.

One manufacturer has recently introduced a transport-type tractor,

shown in Fig. 1, to be used interchangeably with a two-row corn pickersheller and a grain combine. These harvesting machines are mounted

and dismounted on the tractor by the aid of a hoist-frame and iron transport wheels for each of the units.

Manufacturers are now concentrating heavily on the development of

hydraulic systems for use in steering, for use in mounting and dismounting implements quickly and easily, and to serve as a substitute for hand-



FIQ.1. A picker-sheller, mounted 011 a t.ransport-type tractor. The tractor can

also be used to transport a combine. The manufacturer claims that changing the

attachments requires only about 30 minutes. (Courtesy of Minneapolis Moline

Company.)



lever controls. I n a few instances, electrical controls are combined with

hydraulic control systems. I n order to keep the fuel-use efficiency of

the tractor engine high, some of the manufacturers are providing a means

f o r disconnecting the drive to the hydraulic pump when it is not needed.

Methods for changing the drive-wheel spacing semiautomatically on

row-crop-type tractors are being provided by a few manufacturers.

Lack of good stability in the high-clearance row-crop-type tractor is

causing both manufacturers and safety specialists considerable concern.

Only two solutions have been proposed, first, the development of farming systems which eliminate tractor work in row crops and, second, that

of easily operated devices for spreading the tractor wheels laterally so



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L. W. HURLBUT



that they will provide greater stability in the tractor while it is not

being operated in row crops.

It appears that in the near furture most of the tractors will be built

in compliance with the ASAE-SAE standard specifications (1944) for

power take-off and drawbar hitch location and construction. Compliance with these standards makes it' possible for the operator to use any

make of power take-off driven machine with any make of tractor. The

standards also include specifications for providing and connecting the

shields along the power-shafting.

b. Electric Power. Electricity will, undoubtedly, find much greater

use on American farms during the next decade. The number of uses

for electricity on the farm increased from about 35 in 1925 to more than

250 a t present. The number of domestic uses are greatest a t the present

time, but near that number are the uses in crop, animal, and poultry

production. It appears that electric power on the farm will help to

make crop-drying practical, and that in turn may result in important

changes in some grain and hay harvesting and storage practices.

The heat pump provides one of the most challenging and interesting

applications of rural electric power yet developed. The heat pump, as

the name implies, can be used to transfer heat into or out of a given

space. I n the farm home or other buildings it would provide heat during

the cold season and remove excess heat during the warm season. However, before the cost of this equipment and its operation can be reduced

to the economical range for general use, several technical mechanical

and electrical problems must be solved. Johnson (1951) discusses such

problems and, i n addition, proper heat source, house design, reliability,

and serviceability. It is quite possible that widespread use of the heat

pump may develop during the next decade.

0. The Airplame. As a source of power for executing agricultural

operations, the airplane will undoubtedly come into much greater prominence during the next decade. More economical and effective dispersing of dusts, fertilizers, seeds, and sprays by aircraft is indicated in

research results being obtained by the Texas Engineering Experiment

Station (1952). The first phase of the research culminated in the design

and construction of an experimental airplane (Fig. 2) that is designed

to meet the requirements specified by agricultural pilots,

Lehmann (1952) assembled information on the agricultural use of

airplanes. His report indicates that about 5,000,000 acres of farm land

were treated in California by aircraft in 1951. The area treated was

almost double that treated the previous year. The Kansas reports

showed an increase from 419,500 acres in 1948 to an estimated 1,000,000

acres in 1950. There have been similar increases in other areas,



PROURESS IN AGRICULTURAL ENQINEERINO



193



FIQ.2. An experimental airplane designed to meet the requirements specified by

agricultural pilots. Provision is made f o r a quick change of equipment in preparation

for either dusting or spraying. (Courtesy of Texas Agricultural Experiment Station.)



2. #oil and Water Management



It is a well-recognized fact that variations in weather have a great

influence on the yield of crops. Thus far enough has been learned about

this problem to indicate ways in which the farmer may, in a measure a t

least, reduce the damaging effects of weather irregularities. Such measures include drainage, irrigation, improved infiltration and water-holding capacity of soils, and advanced practices for conserving the top soil.

a. Surface-Mulch Farming. The ways in which crop residues on the

surface of the soil aid in maintaining a high water-infiltration rate, the

conditions under which they reduce evaporation, the extent to which

they prevent soil loss, and the extent to which they influence crop yields

as compared to other methods of soil management, are subjects that

have been discussed by Dnley and Russel (1939, 1942a, 1947, 1948),

Carter and McDole (1942), and Larsen and Joy (1943). Mulch farming

and related machinery problems have been discussed by Duley and Russel (1942b) and Hurlbut (1950).

I n the surface-mulch farming system, one can quickly recognize all

of the perpetual machinery problems involved in providing time-tested

practices of good crop husbandry plus the problem of working through,

and under, a cover of crop residue. I n general, this practice appears best

adapted to relatively dry or warmer areas, where a small delay in planting time is less serious than in areas with a shorter growing season.

There are a t least two basic problems involved in utilizing crop residues for mulches, and, as one might expect, both of them have agronomic

and engineering implications. They are :first, to provide as good a seedbed a t seeding time as can be had with timely plowing and the usual



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L. W. HURLBUT



secondary tillage operations ; second, to keep the crop residue on or near

the surface of the soil during the sequence of tillage and seeding operations.

The widespread interest of farmers and the active research in mulchfarming indicate substantial adoption of this practice in the future. One

prominent manufacturer is marketing a new stubble-mulch tiller for the

first time in 1953. Poynor (1950) reported the development of this new

tiller (Fig. 3), a multiple-purpose machine designed for use in row



FIG.3. An experimental machine designed for tilling, fertilizing, and seeding

in one operation. The front tillage units are designed t o loosen soil beneath a cropresidue cover and deposit chemical fertilizer in bands. The rear unit consists of

equipment8 for seeding and depositing starter-fertilizer near the seed. (Courtesy

of International Harvester Company.)



crops. It is designed to perform basic tillage, planting, cultivating, and

fertilizing operations. This development also indicates that a serious

effort is being made on the part of industry to simplify the machinery

requirements for producing row crops.

b. Runoff-Water-Control flystems. Advanced engineering techniques

for design of runoff-water-control systems are being studied. New techniques give some promise of reducing the cost of terrace systems and

indicate that such systems can be made more compatible with mechanized farming operations. Farm water-control systema are of the perma-



PROQRESS IN AQRICULTURAL ENQINEERING



195



nent type and have a considerable influence on farming efficiency. They

deserve the attention of a competent designer.

Wittmuss (1950) studied the design of terrace systems on five farms

and found that by relocating terraces, using variable slope in terrace

channels, and relocating waterways, he could accomplish a 28 per cent

(average) reduction in irregular areas; a reduction of 6.6-15.4 per cent

in terrace length required per acre in four out of five fields studied; and

a 28 per cent reduction in length of waterways required per acre. These

data indicate that water-control systems for land areas being operated

under close economic limits should be planned in accordance with good

engineering practices. This means that carefully prepared plans and

design details should be completed prior to the time construction is

started.

c. Irrigation. The real meaning of the term “irrigation farming”

is becoming clearer each year as the results of irrigation research are

compiled and analyzed. It means something more than merely supplementing rainfall. Land and water are two costly resources i n irrigated

areas, and the development of both of them requires special planning in

order that optimum returns may be obtained. The basic decision a

farmer considering irrigation must make rests on whether or not he

wants to become an irrigation farmer. The decision does not rest on

whether or not to build a system that will supply additional water for

his crops. There is a big difference between these two considerations.

Basically the principles of irrigation farming in subhumid areas are

the same as those developed for arid areas, even though somewhat different problems are encountered. The basic requirements from the standpoint of resources are to maintain an optimum level of fertility, to

maintain good soil tilth so that the soil will respond favorably to water,

and to apply the optimum amount of irrigation water on a timely basis.

There is some evidence in recent irrigation research a t the Nebraska

Agricultural Experiment Station that timeliness in irrigation may be

a factor of considerable importance. This is based on the observation

that the efficiency of irrigation in Nebraska is now about 25 per cent

and on the reasoning that if irrigation efficiency could be increased to

50 per cent, it would be possible to double the present usefulness of

water resources. Increased knowledge of the timeliness factor may be

an important step toward this goal. Studies of the timeliness factor are

now under way at several experiment stations.

Some basic research is being devoted to methods of water application,

considering not only the mechanics of water distribution but also the

problem of soil conservation as it is related to methods of irrigation.



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L. W. HURLBUT



Erosion on irrigated lands is a factor that has not yet received the

attention it deserves.

All evidence available indicates a large expansion in irrigated acreages during the next decade. Good irrigation farming is scientific farming of the highest order.

3. Harvesting a.nd Storing Grain



Maximum harvests rather than maximum yields are what the growers

want. Tremendous harvesting and storage losses are reported each year

because of deficiencies in harvesting practices and storage practices.

This area offers the agricultural engineer one of his greatest opportunities to increase efficiency in agricultural production. Agronomic research has been very successful in increasing crop yields and has

advanced much farther than has the agricultural engineers’ knowledge

of harvesting and storage requirements.

a. Some Harvesting and Storage Losses. Fenton and Swanson (1932)

report that replies received from 297 farmers indicated that 60 per cent

of them had suffered damage to wheat in farm storage. The average

amount damaged per farm was estimated a t 1000 bushels. If we consider the four-year period 1927-1930, the amount of wheat unfit for milling arriving from Kansas a t terminal markets varied from 1 bushel in

8 in the years with favorable harvesting weather to 1bushel in 4 in the

unfavorable years. Although this grain is not a complete loss, it is subject to a substantial discount.

Lemley (1951) verbally reported that of 10,037 bins of farm-stored

wheat sampled in 1950 in Nebraska, 1190 were declared ineligible for

loans at the outset because of excess moisture, sprouts, or “sick wheat.’’

During a reinspection in November and December, 334 loans on wheat

which contained about 13.5 per cent moisture were called up for payment because the grain was deteriorating rapidly. These data indicate

that about 15 per cent of the wheat was stored at a moisture level too

high for safe storage. It is not uncommon for farmers to store only the

driest wheat harvested.

Quisenberry (1949) indicates that annual grain losses in the United

States have been estimated at 10-15 per cent of the crop, although no

exact figures are available. He refers to estimates of the Food and Agriculture Organization which indicate that the present world losses of

grain in storage amount to about 26 million metric tons, roughly equivalent to 950 million bushels of wheat per year, or about 6.6 per cent of

the total cereal production of its forty-eight member countries.

The losses of corn occurring in the field and in storage are of considerable economic importance. When ear corn reaches the level of



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PROGRESS IN AGRICULTURAL ENQINEERING



moisture safe for cribbing, the “normal” (expected minimum) field

losses, consisting of shelled corn and ears dropped, increase a t a rate of

about 3 per cent per week f o r a period of about four weeks, with the loss

thereafter increasing a t a rate of about 1per cent per week. The normal

loss a t the earliest safe cribbing time seems to be near 4 per cent. The

expected grain losses, under favorable harvesting conditions, are shown

in relation to kernel and cob moisture content of ear corn. Table I is

based on data reported by Shedd (1933), Smith e t al. (1949), and Kiesselbach (1950), and on unpublished data recorded by Arms and Hurlbut

of the University of Nebraska.

TABLE I

Expected Total Field Loss (Per Cent) of Corn Harvested under Favorable Conditions in Relation to Moisture Content of the Kernels and Cobs



Days after maturity

27

34

41



Crop characteristics



Mature



10



20



Kernel moisture, %

Cob moisture, %

Expected field loss



34

54

1



26

46

2



20*



*



30

4



17.5

24

7



16

21

10



15

19

13



49



-



1.5

17

15



Normal harvest starts at a kernel moisture of 20 per cent.



The amount of damage that occurs to ear corn in storage is not easily

determined because of the large variation in results obtained in different

years. Shedd (1946) studied the effect of moisture content on grades

of corn in crib storage during the period 1937-1946. He found that the

percentage of cribs containing corn with 20.1 per cent moisture or less

varied from year to year as follows : 1937-38, 90 per cent; 1938, 100

per cent; 194041, 89 per cent; 194142, 85 per cent; 1944-45, 35 per

cent; and 194546, 19 per cent. He observed that it is under favorable

conditions only that a moisture level of 20 per cent will assure the production of grade No. 1 or No. 2 by the customary methods of crib storage. The corn stored at 20 per cent moisture or less, in the 360 cribs

observed, graded as follows (on a damage basis only) : No. 1, 36 per cent ;

No. 2, 26 per cent; No. 3, 14 per cent; No. 4, 12 per cent; No. 5, 6 per

cent; and sample grade, 6 per cent. Loss of some of the original good

quality of ear corn subsequent to harvest results from a lack of ventilation. Poor ventilation may be caused by imperfect machine husking

as well as by imperfect storage structures.

Field and storage losses in the production of grasses and legumes are

generalIy recognized as being rather high. The importance of these field

losses is indicated by Grandfield (1951), who collected data from widely



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L. W . HURLBUT



scattered fields of alfalfa in Kansas. He found that with the present

farm methods of harvesting the seed loss ranged from 17 to 46 per cent.

On the other hand, Hanson and Harrison (1950) report that with present

harvesting methods farmers save only about 40 per cent of the alfalfa

seed actually produced.

There is evidence to indicate that grain producers have always been

reluctant to let grain crops stand in the field until they have dried naturally to a moisture content safe for storage. They have made use of

the header, the binder, the swather, and the corn crib as intermediate

steps in their efforts to reap crops at the earliest possible time. These

intermediate harvesting measures and the lack of a continuous and

easily controlled source of power on the farmstead apparently have not

been conducive to the development of equipment and structures suitable

for curing the crops after they have been placed in bulk storage. However, these measures do indicate that the grower considers a n early harvest of considerable economic importance.

Briefly, an important limiting factor in modern grain production is

the inadequacy of 19th-century storage structures used in combination

with 20th-century harvesting machines. At the present time, it appears

that forced-air drying will be a t least a partial answer to this problem.

The problem of harvesting and drying grain containing more moisture

than is permissible for safe, long-time storage is bounded by agronomic

factors governing the time of harvest and by pathologic factors governing the environment in storage. Basic factors to be considered in addition to maturity of the grain and character of the air available are

moisture and temperature of the grain, soundness of the kernels, foreign

material present, and the period of time suitable for drying.

6 . Moisture Limits for Some Harvesting Mwhines. Field tests conducted a t the Nebraska Agricultural Experiment Station during the

period 1948-1951 have demonstrated that the present-day combines and

corn shellers will do a reasonably good job of harvesting oats, wheat,

brome grass, legumes, and corn containing 25 per cent moisture. Wheat

has been combined at 28 per cent moisture ; oats, brome grass, and sweet

clover a t 32 per cent moisture, and corn containing u p to 30 per cent

moisture has been picked and shelled with an improvised trailer-mounted

sheller.

Harold Hummel, a farmer near Fairbury, Nebraska, combined a

3-acre field of brome grass mixed with alfalfa which yielded seed containing about 51 per cent moisture. The seed from another 5-acre field was

harvested with 46 per cent moisture. About 200 bushels of this seed

was dried with unheated air to 12.2 per cent moisture in 84 hours of

fan operation spread over a period of ten days. The seed was dried in



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